The purpose of this study is to evaluate the hemodynamics and adverse event profile in comparison between two treatment arms, one using an admixture of propofol and etomidate at a ratio by volume of 25%/75% (P2E7), and one using an admixture of propofol and etomidate at a ratio by volume of 75%/25% (P7E2), for anesthesia during endoscopic procedures at the Clements University Hospital (CUH) endoscopy lab (Endo).

Procedural/Surgical anesthesia induction, administration and maintenance with propofol combined with etomidate is commonly used in routine clinical practice in patient with compromised cardiopulmonary status. However, there is no definitive trend or understanding from the literature to discern which ratio of admixture is appropriate for providing stable hemodynamics and minimizing side effects for procedural sedation in gastrointestinal endoscopy procedures. Given the increasing volume for gastrointestinal endoscopy, the increasingly older and greater chronic disease burden of the endoscopic patient population, and the increased utilization of anesthesia for endoscopic procedures this clinical trial aims to provide timely, meaningful and impactful guidance and information for the safe conductance of anesthesia in this patient population.

The objectives are to compare the treatment arms, P2E7 and P7E2, in a randomized controlled double-blind trial for anesthesia for endoscopic procedures. Comparison between an admixture of Propofol/Etomidate 75%/25% versus 25%/75% being utilized as principal anesthetic for endoscopic procedures at CUH endoscopy lab.

Propofol and etomidate can be mixed together in a syringe or similar container for up to 24 hours without adversely affecting appearance, pH, particle size and distribution, zeta potential, observation under centrifugation and drug content and impurity demonstrating the mixture to be physically and chemically compatible. Propofol and Etomidate are both FDA approved for induction and maintenance of general anesthesia in adult patients. Propofol and Etomidate in a wide ranging ratio of combinations in admixture have been utilized for general anesthesia induction and maintenance both in regular standard of care daily clinical practice and within a profound number of research trials including up to a ratio of 80% etomidate and 20 % propofol by volume. Therefore the clinical practice of etomidate and propofol in admixture for the induction and maintenance of general anesthesia in adult patients is standard of care and well founded in the anesthesiology literature. However, there are several important questions about which potential ratio of both drugs provides the best combination of favorable cardiopulmonary effects while having an acceptably low incidence of adverse effects. Thus, this current proposed trial is intended to answer several important questions on that matter.

This trial also will have actual blinding of both patients and practitioners at time of drug administration. Propofol is a white liquid and etomidate is a clear liquid. Thus, past trials where either pure drug was given in sequence or at the same time by separate syringes could not have had any blinding because of this obvious physical quality of the medications. Therefore, only a trial involving an admixture of varying ratios of both drugs could possibly hope to achieve actual blinding as is required for rigorous analysis of results without introducing the bias that comes from a lack of true blinding of patients and practitioners.

Inclusion Criteria:

1. Adult patients (age ≥18 years old)
2. Having endoscopic procedure at CUH with anesthesia
3. ASA 3 or above
4. Ejection Fraction test result available

Exclusion Criteria:

1. Known allergies or adverse reactions to study drugs or study drug components or preservatives
2. Patient refusal
3. Clinician refusal
4. Documented cognitive impairments precluding subject ability to consent for themselves unless a surrogate documented legally acceptable decision maker consents for patient participation
5. Prisoner or incarcerated or patients held by law enforcement officials in custody
6. Pregnancy or patient refusal for pregnancy testing or screening (standard UTSW policy and protocol requires pregnancy testing for appropriate patients prior to anesthesia)

1. PHI (name, date of birth, Medical Record number, phone number, email account, admission date)

2. Demographics (Age, height, weight, BMI)

3. Medical history

4. Medication list Intraoperative data collection

   • Time weighted average mean arterial pressure (every 15 minutes calculate average mean arterial pressure for that interval, then end of case calculate mean of all those means for the entire case) Area Under the Threshold for mean arterial pressure (both predefined threshold of 65 mm Hg and for 40% below patient's immediate preoperative MAP)
   • Vasopressor use by number of units (1 unit of vasopressor being defined as 1 unit vasopressor = 100 mcg phenylephrine = 5 mg ephedrine = 0.5 units vasopressin = 5 mcg norepinephrine)

At conclusion of all data analysis and available permanently

Only study personnel

Blinding plan: Either the investigational drug service with the CUH central pharmacy will prepare the admixture syringes or a separate anesthesia staff not involved in subject's case will prepare admixture syringes thus preventing any case personnel involved with subject's case or subject from knowing which admixture is present within syringes for subject's case.